Currently an annular combustion chamber of a gas turbine engine has a number of fuel injectors arranged to supply fuel into the annular combustion chamber. Each fuel injector includes a fuel feed arm which extends generally radially from the annular combustion chamber and through a corresponding aperture in a combustion chamber casing surrounding the annular combustion chamber. Each fuel injector has a pilot fuel nozzle and a main fuel nozzle. An annular main fuel manifold extends circumferentially around the combustion chamber casing and is arranged to supply fuel to the main fuel nozzle of each of the fuel injectors. Two pilot fuel manifolds extend circumferentially around the combustion chamber casing and together are arranged to supply fuel to the main fuel nozzle of each of the fuel injectors. An annular additional fuel manifold extends circumferentially around the combustion chamber casing and is arranged to supply fuel to each of the fuel injectors. The annular fuel manifold is supported from the combustion chamber casing at a number of circumferentially spaced locations by brackets arranged to prevent vibration of the manifold during operation of the gas turbine engine.
Each fuel injector is connected to the annular main fuel manifold by an associated main fuel supply pipe. Each fuel injector is connected to one of the pilot fuel manifolds by an associated pilot fuel supply pipe and each fuel injector is connected to the annular additional fuel manifold by an associated additional fuel supply pipe. Each main fuel supply pipe is connected at a first end to a T-connector on the annular fuel manifold and is connected at a second end to a radially outer end of the feed arm of the fuel injector. Each pilot fuel supply pipe is connected at a first end to a T-connector on one of the pilot fuel manifolds and is connected at a second end to a radially outer end of the feed arm of the fuel injector. Each additional fuel supply pipe is connected at a first end to a T-connector on the annular additional fuel manifold and is connected at a second end to a radially outer end of the feed arm of the fuel injector. The main fuel supply pipes, the pilot fuel supply pipes and the additional fuel supply pipes are rigid and are arranged in a generally S-shaped path from the respective fuel manifold to the fuel injector.
In this arrangement the main fuel supply pipes, the pilot fuel supply pipes and the additional fuel supply pipes are rigid and delicate and occasionally suffer from denting of the fuel pipes, cracking of welds and consequential leakage of fuel. The rigid main fuel supply pipes, the pilot fuel supply pipes and the additional fuel supply pipes also suffer from vibrations. In addition the assembling of the annular main fuel manifold, main fuel supply pipes, pilot fuel manifolds, pilot fuel supply pipes, annular additional fuel manifold, additional fuel supply pipes and fuel injectors into a fully interlocking and sealing alignment is time consuming and costly and similarly the repairing or replacing of a fuel injector and/or fuel pipe is costly and time consuming. This arrangement requires many components e.g. fuel pipes, connectors, brackets, fasteners, seals etc.
Therefore the present disclosure seeks to provide a novel fuel manifold and fuel injector arrangement for a combustion chamber which reduces or overcomes the above mentioned problem.